The invention relates to a sensor for angular motion, in particular for the use as a yaw rate sensor.
There are motor vehicle control systems that require information on the yawing motion of the vehicle, specifically through the vehicle's movements around the vertical axis. These include, for example, vehicle stability control systems (FSR, ASMS). Other motor vehicle control systems, such as anti-lock braking systems (ABS), drive slip control systems (ASR), etc. can be improved by accounting for yawing motion. Information on pitching and rolling motions is also advantageous for certain motor vehicle control systems.
However, measuring yawing motion presents difficulties. Yawing motion sensors are expensive, especially when they are expected to provide a high degree of reliability, resolution and measuring precision. However, the price of the individual components plays a decisive role, particularly in motor vehicle control systems.
Proposals have already been made involving the use of the balance weights and rotating masses already present in the vehicle to measure yaw rates or yaw torques as input variables for motor vehicle control systems. According to these proposals, measuring and analysis equipment can be used to transform the balance weights and rotating masses into yaw rate and yaw torque sensors. example, the centrifugal mass of the vehicle engine or of a rotating mass located in a tape recorder, CD player or other electronic device may be used to achieve the desired outcome.
If no cost-effective yaw rate sensors are available, shear forces in anti-lock control systems are determined indirectly using complex calculations that are based on wheel RPM data (RPM=rotations per minute). Based on the current level of technology, however, yaw rate sensors are indispensable in other control systems, such as vehicle stability control systems.
The objective of the invention is to develop a sensor for measuring yawing, pitching or rolling motion, i.e. angular motion, particularly for measuring yaw rates or yaw torques, that is relatively inexpensive, operates reliably and delivers signals that can be processed relatively easily.